Quantitative assessment of the contribution of high resolution mass spectrometric analysis to the reliability of compound confirmation.

Applications of high resolution mass spectrometry (HRMS) in food safety and residue analysis have increased remarkably over the last few years. The high resolution detection of ions reportedly enhances the assay selectivity but quantitative assessment of HRMS contribution to the assay selectivity has not yet been undertaken. We devised a method to assess the impact of instrument resolution on the probability that a spectral assignment to a given compound was made in error. The method allows for evaluating the quality of a spectral assignment based on resolution and the number of fragmentation stages. It thus provides a firm basis for comparing analytical methods performed on very different mass spectrometric instrumental platforms as well as in the context of the current regulatory framework.